The CMUcam Vision Sensor   
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If the CMOS camera has a resolution of 352 x 288 pixels, why is the CMUcam resolution only 80 x 143?

    The issue here is how color digital cameras work. In all digital color cameras (even the very expensive ones - except for some based on some very new technology) you only get one color channel measurement per pixel location, this is called mosaic filtering. Here is a nice diagram which helps explain this:

    (Diagram courtesy of Foveon Inc.)

    So what you can see is that pixels can be thought of being arranged in groups of fours, where there are two G measurements and one R and one B measurement per group. If you discard one of the G measurements (which we do) you see that the real resolution of a 352x288 camera is closer to 176x144. We run the camera in half resolution mode which skips over every other 2x2 block horizontally which gives you 88x144. Because of memory limitations in the processor we discard 8 columns horizontally and one row vertically that contains a test pattern which gives you 80x143 as the final resolution.

    Just FYI standard digital cameras use complex interpolation techniques to try to fill in the missing color values at each pixel and give you something a little closer to the full resolution of the sensor.

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